CCD revolutions in astronomy

Transcription

Galaxy Clusters +
Gravitational Lensing
︸
Gamma-ray Bursts, Black Holes, and Exoplanets:
How CCD Detectors have Revolutionized Astronomy
George R. Ricker
MIT Kavli Institute for Astrophysics and Space Research
APS March Meeting
Boston MA
27 February 2012
G. Ricker--27 February 2012
APS March Meeting 2012– Boston MA
1
The Story of Four Graduate Students...
2
Why these Four Graduate Students?
• Each student:
– Developed a major new astronomical instrument in
the MIT CCD Laboratory
– Completed his MIT PhD in Physics based on
astronomical observations with that instrument
– Devoted his subsequent career to astronomical or
detector research
• My story will relate:
– What each student accomplished in his research
– What each student is working on now
4
3
Dramatis Personae and Timeline
1985
2003
CA
AN
D
H E RA
TE2
Nat
Butler
CH
AS
ICC
BR
MA
SC
OT
Roland
Vanderspek
1980
1989
Gerry
Luppino
1995
Keith
Gendreau
A Story in Four Acts...
Act 1: Roland Vanderspek
“Multicamera CCD Sky Surveys”
Featuring Optical Flashes, GRB counterparts, and Transiting Exoplanets
...ETC ➔ HETE-2 ➔ TESS
Act 2: Gerry Luppino
“Large FOV CCD Arrays”
Featuring Galaxy Clusters and Gravitational Lensing
...Ever larger (!) FOV CCD arrays
Act 3: Keith Gendreau
“X-ray CCDs in Space: Modest FOVs”
Featuring Cosmic X-ray Background, Pulsars, Laboratory Astrophysics
...ASCA ➔ Astro-D ➔ NICER
Act 4: Nat Butler
“X-ray CCDs in Space: Large FOVs”
Featuring X-ray Flashes, Dark GRBs, Collapsars, and Shredded Stars
... HETE-2 ➔ Swift ➔ RATIR
GRB = Gamma-ray Burst
Other acronyms defined later
5
“Multicamera CCD Sky Surveys”
Featuring optical flashes, GRB counterparts, and transiting
exoplanets
...ETC ➔ HETE-2 ➔ TESS
(MIT PhD 1985; currently MKI Research Scientist)
6
Roland and MASCOT at KPNO 4 meter Telescope
MASCOT= MIT Astronomical Spectroscopy Camera for Optical Telescopes
–
–
–
–
Enabled simultaneous imaging and long slit spectroscopy
One of earliest dual CCD system
Lightweight, compact system
Traveling instrument, deployed on many telescopes in early 1980’s:
Kitt Peak 4m; CTIO 4m; Mauna Kea 2.2 m; MDM 2.4 m
7
Roland’s Thesis Abstract
8
Explosive Transient Camera (ETC) Basic Idea
ETC Side View
ETC Camera Assembly Line
ETC Fields-of-View on Sky
Vanderspek et al 1992
9
ETC with Roland
10
ETC Results
• Technical Challenges
– Pioneering Effort
– Telescope in Arizona operated from Cambridge in
fully-robotic manner
– Limited RAM (~ 0.5 MB) and slow (~10 MHz) CPUs
– Pre-Internet with dial-up modems
• Survey Limits
– Tumbling Satellites & Orbital Debris
– Limits on Optical Flashes from GRBs (w. BATSE)
• Look ahead
– Optical methods needed to support satellite
missions that would crack the GRB counterpart
problem 15 years later
– Template for Beppo-SAX, HETE-2, and Swift
Followup Networks
11
“Large FOV CCD Arrays”
Featuring Galaxy Clusters and Gravitational Lensing
...Ever larger (!) FOV CCD arrays
(MIT PhD 1989; recently Professor of Astronomy, University
of Hawaii; currently President & CEO, GL Scientific)
12
Gerry and MASCOT at Kitt Peak
13
IDENTIFICATION AND STUDY OF DISTANT GALAXY CLUSTERS
Gerry’s Thesis Abstract
by
GERARD A. LUPPINO
2
SUBMITTED TO THE DEPARTMENT OF PHYSICS OF THE MASSACHUSEITS INSTITUTE OF TECHNOLOOY
ON AUGUST 1989, IN PARTIAL FULFILLMENf OF THE REQUIREMENTS FOR THE DEGREE OF
IXJCTOR OF PlllLOSOPHY IN PHYSICS
DESIGN AND USE OF A LARGE-FORMAT CCD INSTRUMENT
FOR THE
IDENTIFICATION AND STUDY OF DISTANT GALAXY CLUSTERS
by
GERARD A. LUPPINO
SUBMITTED TO THE DEPARTMENT OF PHYSICS OF THE MASSACHUSEITS INSTITUTE OF TECHNOLOOY
ON AUGUST 1989, IN PARTIAL FULFILLMENf OF THE REQUIREMENTS FOR THE DEGREE OF
IXJCTOR OF PlllLOSOPHY IN PHYSICS
ABSlRACT
This dissertation describes a search for distant clusters of galaxies (z>0.3). Cluster candidates were selected
from a sample of radio sources with steep, low-frequency spectra since such radio sources are often found in rich
nearby galaxy clusters. The steep-spectrum radio source (SSRS) is thought to be produced by the confinement
of the radio plasma by the thermal pressure of a hot intracluster gas; therefore, we expect clusters discovered by
this selection criterion to be bright x-ray sources and excellent targets for future x-ray satellites such as ROSAT,
ASTRO-D and AXAF. These objects are also more likely to be true physical associations rather than the
chance superpositions of galaxies that may plague some optically selected samples, particularly those at faint
magnitudes. In order to identify the optical counterpart of the SSRS and see if the radio source was part of a
distant cluster of galaxies, optical images to faint limiting magnitudes were required. Therefore, an imaging
instrument incorporating mosaics of CCOs was designed and built. With this instrument, it is possible to
observe faint, distant clusters of galaxies with spatial resolution limited by atmospheric seeing, while at the
same time covering a relatively large field of view.
The major task in the creation of this instrument was the design and construction of two separate CCD
camera systems; each based on different CCO mosaics. The rust camera system incorporates four prototype, TI
850 x 750 virtual-phase CCDs (22.3 J..lIll square pixels) arranged in a square pattern with the device packages
abutted. The second camera system is designed to operate a four-chip CCD imager made by MIT Lincoln
Laboratory. The imaging area of this CCD mosaic is 840 x 840 pixels (27 J..lIll square pixels) formed by
abutting four 840 x 420 framestore devices with seam losses less than 6 pixels. Oetails of the CCO camera
electronics design as well as details of the mechanical design of the CCO cameras and LN2 dewars are described.
A total of 30 SSRS fields were observed with this CCO instrument mounted on the 1.3m and 2.4m
telescopes of the Michigan-Oartmouth-MIT (MOM) Observatory on Kitt Peak. Additional CCO images of 5 of
these radio sources were obtained with the Kitt Peak 4m telescope equipped with the KPNO prime focus CCD.
Of these 30 SSRSs, 26 have been optically identified. In all, 15 of the observed fields contain visible clusters
of galaxies, some of which are quite rich. Of the remaining 15 SSRSs, 6 are identified with faint galaxies, 2
are identified with poor groups, 3 are probably quasars, and 4 of the fields have uncertain or no optical
counterpart. The median value for the estimated redshift of the 15 clusters is z=0.43 and the median richness is
Abell Class 2. Nearly all of the radio sources have classical double-lobed morphology, and in half of the
sources associated with clusters, the radio source is identified with a fainter cluster member rather than with the
brightest cluster galaxy. In all cases where the cluster is BM Type I, however, the radio source is identified with
the optically dominant galaxy.
ABSlRACT
This dissertation describes a search for distant clusters of galaxies (z>0.3). Cluster candidates were selected
from a sample of radio sources with steep, low-frequency spectra since such radio sources are often found in rich
nearby galaxy clusters. The steep-spectrum radio source (SSRS) is thought to be produced by the confinement
of the radio plasma by the thermal pressure of a hot intracluster gas; therefore, we expect clusters discovered by
this selection criterion to be bright x-ray sources and excellent targets for future x-ray satellites such as ROSAT,
ASTRO-D and AXAF. These objects are also more likely to be true physical associations rather than the
chance superpositions of galaxies that may plague some optically selected samples, particularly those at faint
magnitudes. In order to identify the optical counterpart of the SSRS and see if the radio source was part of a
distant cluster of galaxies, optical images to faint limiting magnitudes were required. Therefore, an imaging
instrument incorporating mosaics of CCOs was designed and built. With this instrument, it is possible to
observe faint, distant clusters of galaxies with spatial resolution limited by atmospheric seeing, while at the
same time covering a relatively large field of view.
The major task in the creation of this instrument was the design and construction of two separate CCD
camera systems; each based on different CCO mosaics. The rust camera system incorporates four prototype, TI
850 x 750 virtual-phase CCDs (22.3 J..lIll square pixels) arranged in a square pattern with the device packages
abutted. The second camera system is designed to operate a four-chip CCD imager made by MIT Lincoln
Laboratory. The imaging area of this CCD mosaic is 840 x 840 pixels (27 J..lIll square pixels) formed by
abutting four 840 x 420 framestore devices with seam losses less than 6 pixels. Oetails of the CCO camera
electronics design as well as details of the mechanical design of the CCO cameras and LN2 dewars are described.
A total of 30 SSRS fields were observed with this CCO instrument mounted on the 1.3m and 2.4m
telescopes of the Michigan-Oartmouth-MIT (MOM) Observatory on Kitt Peak. Additional CCO images of 5 of
these radio sources were obtained with the Kitt Peak 4m telescope equipped with the KPNO prime focus CCD.
Of these 30 SSRSs, 26 have been optically identified. In all, 15 of the observed fields contain visible clusters
of galaxies, some of which are quite rich. Of the remaining 15 SSRSs, 6 are identified with faint galaxies, 2
are identified with poor groups, 3 are probably quasars, and 4 of the fields have uncertain or no optical
counterpart. The median value for the estimated redshift of the 15 clusters is z=0.43 and the median richness is
Abell Class 2. Nearly all of the radio sources have classical double-lobed morphology, and in half of the
sources associated with clusters, the radio source is identified with a fainter cluster member rather than with the
brightest cluster galaxy. In all cases where the cluster is BM Type I, however, the radio source is identified with
the optically dominant galaxy.
Observations are also presented of three distant clusters that were not part of the radio selected sample:
0414+009, an x-ray bright BL Lac object coincident with the optically dominant galaxy in a Richness Class 1
cluster; 1217+1006, a compact group containing an extremely blue (B-R) == 0.0 object that may be either a
QSO or a BL Lac; and 1358+6245, a new, x-ray luminous (Lx (0.5-4.5 keY) =
erg s-l), extremely
rich (Richness Class 3 or 4), distant cluster of galaxies (z=O.323) which exhibits the Butcher-Oemler effect with
a blue galaxy fractionib =0.18 orib =0.10 depending on the background galaxy correction.
Observations are also presented of three distant clusters that were not part of the radio selected sample:
0414+009, an x-ray bright BL Lac object coincident with the optically dominant galaxy in a Richness Class 1
cluster; 1217+1006, a compact group containing an extremely blue (B-R) == 0.0 object that may be either a
QSO or a BL Lac; and 1358+6245, a new, x-ray luminous (Lx (0.5-4.5 keY) =
erg s-l), extremely
rich (Richness Class 3 or 4), distant cluster of galaxies (z=O.323) which exhibits the Butcher-Oemler effect with
a blue galaxy fractionib =0.18 orib =0.10 depending on the background galaxy correction.
14
Gravitational Lensing in a Triple Cluster of Galaxies
Luppino et al.(2008)
15
Gerry Builds CCD Arrays!
© National Geographic 1994
16
Canada-France-Hawaii Telescope 12K x 8K Array (ca 1998)
17
“Gerry’s Law” for CCD Camera Arrays
Array systems
built or
consortia
CCDs
produced by
Gerry
Pixel Count in
astronomical
arrays doubles
every 2 years!
18
“X-ray CCDs in Space: Modest FOVs”
Featuring Cosmic X-ray Background, Pulsars, Laboratory Astrophysics
...ASCA ➔ Astro-D ➔ NICER
(MIT PhD 1995; currently NASA Goddard Astrophysicist)
19
Keith’s Thesis Abstract
20
X-ray Sky: Source Environment
 X-ray sky is very dark
- 106 times lower surface brightness than optical sky
- Photon flux equivalent to V=+40 mag arcsec2
- Blocked by earth’s atmosphere—must go to space
 Thus, a few X-rays from a point source can be
very significant
- Photon-counting detectors are essential
- Detectors should provide spatial, temporal, and
energy information for each detected photon!
- Examples:
- ASCA’s CCD detector provides energy
measurements in ~50 “X-ray colors”
simultaneously
- HETE-2’s CCD camera can establish ~10” source
locations with only a dozen X-ray photons
21
Photon
Absorption
Depth
in
Silicon
Absorption Depth of Silicon
~15 keV-0.15 keV: X-ray CCD Range
Figure from J. Beletic 2012
22
X-ray CCD: Principles of Operation
where:
ΔEFWHM = Energy resolution (eV)
N = readout noise (electrons RMS)
F = Fano factor (~0.1 for Si)
Ex = X-ray energy (eV).
(~1990)
B, C, N, O, F, Ne, Na, Mg, Al, Si, P,
S, Cl, Ar, K, Ca, Sc, Ti, V, Cr, Mn, Fe,Co, Ni,
Cu, Zn, … Ag well-separated
CCD Readout Noise: Effect on Spectral Resolution
Resolution ( FWHM in eV )
140
120
RMS Noise:
100
80
1 e2 e-
60
3 e4 e5 e10 e-
40
20
0
0
1000
2000
3000
4000
5000
Energy ( eV )
23
X-ray Photopeak Resolution in MBE BI X-ray CCD
Counts per Bin (normalized)
MIT/LL CCID48
Boron K
z=5
Carbon K
z=6
Nitrogen K
z=7
Oxygen K
z=8
48 eV
FWHM
“world’s
record”
53 eV
FWHM
24
Flight Heritage: MIT X-ray CCD Detectors
Photo
Satellite
Program
X-ray CCD
Detector
Advanced Satellite
for Cosmology &
Astrophysics
(ASCA) —Solid
Sate Imaging
Spectrometer
(SIS)
Launched
Camera Remarks
LL CCID-7: Two
Hybrid Focal Planes;
420 x 420 arrays; 8
devices Total
Feb 1993
Japan-US; 8 year operations
(satellite re-entry);
developed, constructed at
MIT
Chandra X-ray
Observatory —
Advanced CCD
Imaging
Spectrometer
(ACIS)
LL CCID-17:
Mosaiced Focal
Plane; 1K x 1K
arrays; 10 Devices
Total
Jul 1999
NASA “Great Observatory”
principal imager; 12+ years
operations (ongoing);
MIT
High Energy
Transient
Experiment (HETE)
— Soft X-ray
Camera (SXC)
LL CCID-20: Two
Mosaiced Focal
Planes; 2K x 4K
arrays; 4 Devices
Total
Oct 2000
US-Japan-France gammaray burst observatory; 6
years operations; satellite
bus and SXC developed,
constructed at MIT
AstroE2—X-ray
Imaging
Spectrometer (XIS)
LL CCID-41: Single
Device Focal Planes;
1K x 1K arrays; 4
Devices Total
Jul 2005
Japan-US; successfully
commissioned; 6+ years
operations (ongoing); focal
plane, electronics
MIT
All MIT Lincoln Lab CCDs
25
ASCA SIS X-ray Camera
Solid State Imaging Spectrometer (SIS) for the ASCA Satellite
(...First photon-counting CCD array flown in space)
26
ASCA (= Astro-D) Launch
ASCA launched from ISAS’s Kagoshima Space Center on 20 February 1993
(Reentry on 2 March 2001)
27
Keith Celebrating with ISAS Colleagues
28
ASCA/SIS Cosmic Diffuse X-ray Background Result
ASCA/SIS (Gendreau et al. 1995)
Einstein Observatory (Wu et al. 1991)
HEAO1-A2 Observatory (Marshall et al. 1980)
Galactic
Excess
Powerlaw Model
(Extragalactic)
29
1985
2003
CA
AN
D
H E RA
TE2
Nat
Butler
CH
AS
ICC
BR
MA
SC
OT
Roland
Vanderspek
1980
1989
Gerry
Luppino
1995
Keith
Gendreau
NICER on ISS 2016
30
Keith’s Recent Initiative: NICER Mission
NICER will measure stellar radii, a key distinguisher between true neutron
stars and currently indistinguishable alternatives such as quark stars.
31
Photo
Satellite
Program
X-ray CCD
Detector
Advanced Satellite
for Cosmology &
Astrophysics
(ASCA) —Solid
Sate Imaging
Spectrometer
(SIS)
Launched
Camera Remarks
LL CCID-7: Two
420 x 420 arrays; 8
devices Total
Feb 1993
MIT
Chandra X-ray
Observatory —
Advanced CCD
Imaging
Spectrometer
(ACIS)
LL CCID-17:
Mosaiced Focal
Plane; 1K x 1K
arrays; 10 Devices
Total
Jul 1999
MIT
High Energy
Transient
Experiment (HETE)
— Soft X-ray
Camera (SXC)
LL CCID-20: Two
Mosaiced Focal
Planes; 2K x 4K
arrays; 4 Devices
Total
Oct 2000
constructed at MIT
AstroE2—X-ray
Imaging
Spectrometer (XIS)
LL CCID-41: Single
1K x 1K arrays; 4
Devices Total
Jul 2005
plane, electronics
MIT
32
Chandra ACIS — Two Views
CCDs viewed from the X-ray Telescope
CCD Flight Focal Plane Assembly
Chandra launched successfully by Space Shuttle Columbia on 23 July 1999; ACIS still operating well
33
ACIS Observations of Galactic Center (Sgr A Complex)
Fe Ka Fluorescent Feature: Light Echo?
Sgr A West HII Region
Sgr A East SNR
FOV has ~2000
Cataclysmic Variables
& X-Ray Bursters
Bipolar
Outflow?
1’ = 7.5 light-yr
Nonthermal
Filament
Bagenoff et al. 2003
34
Crab Nebula over Seven Months with ACIS
Weisskopf et al 2011
35
Act 4: Nat Butler
Act 4: Nat Butler
“X-ray CCDs in Space: Large FOVs”
Featuring X-ray Flashes, Dark GRBs, Collapsars, and Shredded Stars
... HETE-2 ➔ Swift ➔ RATIR
(MIT PhD 2003; currently Assistant Professor, Arizona State University)
36
Nat’s Thesis Abstract
37
Photo
Satellite
Program
X-ray CCD
Detector
Advanced Satellite
for Cosmology &
Astrophysics
(ASCA) —Solid
Sate Imaging
Spectrometer
(SIS)
Launched
Camera Remarks
LL CCID-7: Two
420 x 420 arrays; 8
devices Total
Feb 1993
MIT
Chandra X-ray
Observatory —
Advanced CCD
Imaging
Spectrometer
(ACIS)
LL CCID-17:
Mosaiced Focal
Plane; 1K x 1K
arrays; 10 Devices
Total
Jul 1999
MIT
High Energy
Transient
Experiment (HETE)
— Soft X-ray
Camera (SXC)
LL CCID-20: Two
Mosaiced Focal
Planes; 2K x 4K
arrays; 4 Devices
Total
Oct 2000
constructed at MIT
AstroE2—X-ray
Imaging
Spectrometer (XIS)
LL CCID-41: Single
1K x 1K arrays; 4
Devices Total
Jul 2005
plane, electronics
MIT
38
Assembly of HETE-2 Soft X-ray Camera (SXC)
Coded Mask
X-ray CCDs
Optical Star
Camera
39
Schematic of HETE-2 Soft X-ray Camera (SXC)
X-rays
Star Field
Optical Blocking Filter
(77 nm Al on 500 nm polyimide)
Coded Mask, 30 µm Gold
Lens
25 µm Be Shield on 1 CCD
2 x CCID-20 on Aluminum
Nitride Baseplate
CCID-22
Mask to Detector Distance = 100 mm
CCD Pixel Size= 15µm
40
Mask Pattern Correlation for HETE-2 SXC
Entire
Correlation
Space
NB:
1 correlation
step
is ~ 30”
Close-up of
Correlation
Peak
∴ ∼3-5” locations
achievable for high
S/N detections
in SXC
41
SXC Flight Unit on HETE-2 Satellite
SXC=
Soft X-ray
Camera
OBC=
Optical
Boresight
Camera
42
Nat’s Preparation for HETE-2 Launch
MIT CCD Group:
Nat
--Constructed the SXC and optical cameras
--Built the spacecraft bus
--Integrated & tested the instruments & bus
--Developed a dedicated HETE-2 telemetry network
--Participated in the launch
--Operated the satellite 24/7
--Analyzed & published the science data
(with HETE-2 Science Team)
43
Launch of HETE-2 on a Pegasus Rocket
44
HETE-2 GRB MicroSat (125 kg): Operated 2000-2006
45
HETE-2 Gamma-ray Bursts: Six Major Scientific Insights
GRB020531:
FREGATE DATA, 20ms resolution, 30-400 keV
3000
2500
t50= 0.36 s
2000
First detection of short GRB with
prompt optical/X-ray followup
1500
1000
500
0
-5
-4
-3
-2
-1
0
1
2
3
4
GRB021211:
5
Time (s)
ar
D
Insight into “Optically
Dark” GRB Mystery
k
ur
B
s
st
GRB020903:
Elucidation of
“X-ray Flashes”
GRB030329:
T50 = 70 ms
GRB-SN Connection
(SN2003dh; z=0.168)
GRB021004:
Refreshed shock
or inhomogeneous jet
GRB050709:
Short-hard GRB
identified (z=0.16)
46
Nat’s Recent work: SN2011fe in Whirlpool Galaxy
Li et al. , Nature, 480, 348-350 (15 December 2011)
Conclusion: Luminous red giant companion is excluded a progenitor to youngest Type 1a supernova ever discovered
47
1985
2003
TESS
2017
CA
AN
D
H E RA
TE2
Nat
Butler
CH
AS
ICC
BR
MA
SC
OT
Roland
Vanderspek
*
1980
1989
Gerry
Luppino
1995
Keith
Gendreau
48
Transiting Exoplanet Survey Satellite (TESS)
TESS
49
Ricker/MIT
What is TESS?
TESS is an Explorer Class Mission selected by NASA in 2011 for Phase A Study
➡
Previously selected for Phase A in last SMEX round
➡
Launch planned in 2016
TESS will conduct the first All Sky Exoplanet Search from space
➡
Two year survey duration
➡
Targets stars brighter than ~12 magnitude
TESS is low cost and simple in design
➡
TESS
Payload has four wide FOV cameras
50
Clampin/GSFC
Ricker/MIT
TESS Camera Assembly
DETECTOR ASSEMBLY
4096 by 4096 pixels
16.8 Mpixels CCD Array
LENS
150mm Focal Length
f / 1.5
LENS HOOD
TESS has a low cost, simple design
based on four wide FOV cameras
TESS
51
Ricker/MIT
TESS Science Legacy
TESS will discover new exoplanets transiting the “best
stars” for followup: the nearest and brightest stars
➡
TESS will monitor 500,000 stars
➡
TESS science goals focus on
➡
Earths and super-Earths (<2.0 RE)
➡
Host stars with stellar types F5 to M5
TESS provides ELTs and JWST with the very best exoplanet targets
for detailed characterization
TESS
52
Ricker/MIT
Thank You!
53

CCD revolutions in astronomy

Transcription

Similar documents

Fact Sheet

Rally Flyer - The Massachusetts Teachers Association

Health Justice for Boston Number 2

Untitled - Chaplin Entertainment, Inc.

E-Health and Digital Services Boston Children`s Hospital

Epoxy Intumescent Fireproofing Systems

rose fitzgerald kennedy greenway financial district

Boston Jun - Clint Hamblin Biography_Home

“How to Become a Writer” by Lorrie Moore from Charters, Ann, Ed

Keith Mascoll in GRIMM